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-   -   My trans loves drive. (https://www.fuelly.com/forums/f11/my-trans-loves-drive-12141.html)

GasSavers_Scott 11-24-2009 08:16 PM

My trans loves drive.
 
When I first got the Focus, I did every trans trick I knew, coasting in netrual, staying out of over drive in the city, poping it into neutral at red lights, and manually shifting all the gears.

Well coasting in neutral just about knocks your teeth out when you put it back in gear, I even tried matching RPM, that just made a larger clunk. Staying out of over drive would leave the trans stuck in second gear, I'd have to come to a stop, go to neutral, then drive and it would go back to shifting normally. Poping it into neutral at red lights works, but showed no MPG changes. Manually shifting the gears got worse mileage.

Now I know some trans respond well to all the tricks, but mine just want's to be left in drive. All my good MPG comes from staying below 70, drafting trucks, rolling on the throttle gently, making a WAI, and swithcing to a Synthetic blend.

If you ever had a chance to drive one of the new Malibu's, it feels like a 6 speed, I think it has 3 planetaries and uses the lock up feature between gears to make 6 speeds, always keeping the engine around 2000 RPM. The Focus has a 3 speed trans with a lock up, but brings in the lock up at 2nd and 3rd, effectivly making a 5 speed auto. Also it has a free wheel thing on the freeway, when you back off the throttle, the engine coasts at 2000 PRM till you give it gas again. I get the best MPG by just leaving it in drive.

theholycow 11-25-2009 02:25 AM

:( Bummer about all that. Some automatic transmissions just don't like to cooperate. My wife's 2000 Isuzu Rodeo reportedly behaves similarly, and also overheats in neutral with the engine still running.

Quote:

Originally Posted by Scott (Post 144479)
If you ever had a chance to drive one of the new Malibu's, it feels like a 6 speed, I think it has 3 planetaries and uses the lock up feature between gears to make 6 speeds, always keeping the engine around 2000 RPM.

Late-model Malibus (and many other late-model GMs) have 6 speed automatic transmissions. If you count lockup, it would be more than 6 speeds.

Quote:

The Focus has a 3 speed trans with a lock up, but brings in the lock up at 2nd and 3rd, effectivly making a 5 speed auto.
I'm pretty sure there were no 3 speed transmissions on the market when the Focus came out. Your 2002 almost certainly has a 4 speed, in which case you are only feeling lockup in 4th hence why it feels like 5 speeds. Lockup isn't on/off in modern vehicles, it's eased in smoothly, so it may be difficult to notice, and it may never fully lock in anything other than high gear. I'm not sure if/when the Focus was offered with a 5 or 6 speed automatic.

Quote:

Also it has a free wheel thing on the freeway, when you back off the throttle, the engine coasts at 2000 PRM till you give it gas again. I get the best MPG by just leaving it in drive.
If it was freewheeling, it would go down to idle. 2000 RPM tells me that it's just your torque converter coming unlocked. What's your RPM before you get off the gas?

bobc455 11-25-2009 11:59 AM

I've tried the neutral trick on several cars, and although I've never experienced mechanical problems I don't think it helps much either. If I was driving an old-school 3-speed automatic with short gears (i.e. 3.42), there might be some benefit to going into neutral and letting the revs drop on a downhill. But with today's overdrives, I don't think it has any benefit. I just set the cruise control for the lowest speed that I don't interfere with traffic flow.

-Bob C.

GasSavers_Scott 11-27-2009 05:17 AM

On highway, it cuises 2800 RPM at 70 MPH, when I back off, it stays at 2000 RPM, idle is 700. I didn't know about true 4 and 5 speed autos, I guess they just keep stacking planetaris, thanks for the info. I understand the Prius, eventhough they claim its a CVT its more like a auto 9 speed.

Jay2TheRescue 11-27-2009 05:43 AM

In the summer of 08 I had to put a new torque converter in The Beast. It may have been coincidental, but at the time I was doing a lot of coasting in Neutral, DFCO, and Neutral @ stops.

Since then I have not been as agressive with my hypermiling efforts, especially those that involve shifting the transmission. My ScanGauge does not report any change in fuel flow between stopped in Neutral & stopped in Drive. I have completely removed that from my regimen. I've greatly reduced the amount of DFCO and Neutral coasting that I do as well. Because hypermiling can be a bit hard on the transmission I did have them refill the tranny with synthetic ATF when the new TC was installed. I still don't want to hypermile into the repair shop again. Transmission repairs are expensive on a 4x4.

theholycow 11-27-2009 08:47 AM

I also don't bother using neutral at stops.

Not only are 4 and 5 speed autos common, but they're out of date now with 6 being the new trend (I know they're in most GMs and VWs now, and the other manufacturers probably have them too). 7 and 8 speed autos are on the market now, too. Toyota is putting that 8 speed auto in some Lexus models.

The CVT shouldn't be broken down into speeds, but for the sake of drivers who expect to feel shifts they've programmed many to behave like that. It's supposed to be totally smooth, infinitely variable.

jcp123 11-29-2009 07:20 PM

Yes, your Focus is a four-speed auto; my first car was an '00 ZTS with the Zetec motor and auto. 75mph gets 3k rpm in top. I think you might see some benefit with using neutral at the stoplight, but I wouldn't bother while in motion.

I have the bobc455 aforementioned three speed auto with no lockup, and I get a nice little jarring when the trans shifts back into gear while rolling - I don't do it anymore.

theholycow 11-30-2009 04:49 AM

I've been driving my wife's Isuzu. It doesn't like neutral. She told me about it but I've been trying it myself, it's weird. When you shift to neutral it seems like it downshifts before going to neutral; the tach jumps up and the vehicle slows. However, it doesn't slow as much as downshifting would, and the deceleration doesn't quit when the tach drops to idle. Then when you shift back to D, it jumps up again before settling into gear. It must not be able to shift between 4 and neutral or something.

jcp123 11-30-2009 05:13 PM

Some transmissions are a little TOO good at smoothing the N-D shift out - my Mom's Duratec Escape just held onto the revs in N for an automatic rev-match. Smooth but hardly saved fuel.


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